Scoping work involved in moving all git transactions to Gitaly
Relating to the overarching goal of moving all git transactions to Gitaly for better performance and resilience from NFS failures, I thought it to be a good idea to scope out the effort involved.
- There are 210 git controllers, but they do not map 1:1 to a Gitaly endpoint.
- There are an estimated 100 Gitaly endpoints (see discussion in comments)
- The team at current capacity intends to tackle 24 of those endpoints in Q3. (1 endpoint per person every 2 weeks)
- At the pace of 24 per quarter, it will take ~4 quarters to complete the migration.
- To complete them all in a single quarter would require an ideal onboarding / ramp up to
roundup((100 endpoints/(0.5 * 13 weeks))) = 16people, i.e. add 12. For two quarters, it is 8, i.e. add 4.
Gitaly 10x faster
In light of the slow pathway of the "regular" path calculated above, the Gitaly team got together with @sytses @dzaporozhets and came up with a way to speed things up. Full proposal is being worked on in https://docs.google.com/document/d/1UkEHeKLScqWgbnP97CweAKsQ4q_T79ZgFMO4Jwxh_dg/edit#heading=h.gt8qpfdv8ktx